Tom Underhill
f4de45800f
Summary: This Pull Request implements the PlatformColor proposal discussed at https://github.com/react-native-community/discussions-and-proposals/issues/126. The changes include implementations for iOS and Android as well as a PlatformColorExample page in RNTester. Every native platform has the concept of system defined colors. Instead of specifying a concrete color value the app developer can choose a system color that varies in appearance depending on a system theme settings such Light or Dark mode, accessibility settings such as a High Contrast mode, and even its context within the app such as the traits of a containing view or window. The proposal is to add true platform color support to react-native by extending the Flow type `ColorValue` with platform specific color type information for each platform and to provide a convenience function, `PlatformColor()`, for instantiating platform specific ColorValue objects. `PlatformColor(name [, name ...])` where `name` is a system color name on a given platform. If `name` does not resolve to a color for any reason, the next `name` in the argument list will be resolved and so on. If none of the names resolve, a RedBox error occurs. This allows a latest platform color to be used, but if running on an older platform it will fallback to a previous version. The function returns a `ColorValue`. On iOS the values of `name` is one of the iOS [UI Element](https://developer.apple.com/documentation/uikit/uicolor/ui_element_colors) or [Standard Color](https://developer.apple.com/documentation/uikit/uicolor/standard_colors) names such as `labelColor` or `systemFillColor`. On Android the `name` values are the same [app resource](https://developer.android.com/guide/topics/resources/providing-resources) path strings that can be expressed in XML: XML Resource: `@ [<package_name>:]<resource_type>/<resource_name>` Style reference from current theme: `?[<package_name>:][<resource_type>/]<resource_name>` For example: - `?android:colorError` - `?android:attr/colorError` - `?attr/colorPrimary` - `?colorPrimaryDark` - `android:color/holo_purple` - `color/catalyst_redbox_background` On iOS another type of system dynamic color can be created using the `IOSDynamicColor({dark: <color>, light:<color>})` method. The arguments are a tuple containing custom colors for light and dark themes. Such dynamic colors are useful for branding colors or other app specific colors that still respond automatically to system setting changes. Example: `<View style={{ backgroundColor: IOSDynamicColor({light: 'black', dark: 'white'}) }}/>` Other platforms could create platform specific functions similar to `IOSDynamicColor` per the needs of those platforms. For example, macOS has a similar dynamic color type that could be implemented via a `MacDynamicColor`. On Windows custom brushes that tint or otherwise modify a system brush could be created using a platform specific method. ## Changelog [General] [Added] - Added PlatformColor implementations for iOS and Android Pull Request resolved: https://github.com/facebook/react-native/pull/27908 Test Plan: The changes have been tested using the RNTester test app for iOS and Android. On iOS a set of XCTestCase's were added to the Unit Tests. <img width="924" alt="PlatformColor-ios-android" src="https://user-images.githubusercontent.com/30053638/73472497-ff183a80-433f-11ea-90d8-2b04338bbe79.png"> In addition `PlatformColor` support has been added to other out-of-tree platforms such as macOS and Windows has been implemented using these changes: react-native for macOS branch: https://github.com/microsoft/react-native/compare/master...tom-un:tomun/platformcolors react-native for Windows branch: https://github.com/microsoft/react-native-windows/compare/master...tom-un:tomun/platformcolors iOS |Light|Dark| |{F229354502}|{F229354515}| Android |Light|Dark| |{F230114392}|{F230114490}| {F230122700} Reviewed By: hramos Differential Revision: D19837753 Pulled By: TheSavior fbshipit-source-id: 82ca70d40802f3b24591bfd4b94b61f3c38ba829
RNTester
The RNTester showcases React Native views and modules.
Running this app
Before running the app, make sure you ran:
git clone https://github.com/facebook/react-native.git
cd react-native
npm install
Running on iOS
Both macOS and Xcode are required.
- Install CocoaPods. We installing CocoaPods using Homebrew:
brew install cocoapods - Run
cd RNTester; pod install - Open the generated
RNTesterPods.xcworkspace. This is not checked in, as it is generated by CocoaPods. Do not openRNTesterPods.xcodeprojdirectly.
Running on Android
You'll need to have all the prerequisites (SDK, NDK) for Building React Native installed.
Start an Android emulator.
cd react-native
./gradlew :RNTester:android:app:installJscDebug
./scripts/packager.sh
Note: Building for the first time can take a while.
Open the RNTester app in your emulator.
If you want to use a physical device, run adb devices, then adb -s <device name> reverse tcp:8081 tcp:8081.
See Running on Device for additional instructions on using a physical device.
Running with Buck
Follow the same setup as running with gradle.
Install Buck from here.
Run the following commands from the react-native folder:
./gradlew :ReactAndroid:packageReactNdkLibsForBuck
buck fetch rntester
buck install -r rntester
./scripts/packager.sh
Note: The native libs are still built using gradle. Full build with buck is coming soon(tm).
Running Detox Tests on iOS
Install Detox from here.
To run the e2e tests locally, run the following commands from the react-native folder:
yarn build-ios-e2e
yarn test-ios-e2e
These are the equivalent of running:
detox build -c ios.sim.release
detox test -c ios.sim.release --cleanup
These build the app in Release mode, so the production code is bundled and included in the built app.
When developing E2E tests, you may want to run in development mode, so that changes to the production code show up immediately. To do this, run:
detox build -c ios.sim.debug
detox test -c ios.sim.debug
You will also need to have Metro running in another terminal. Note that if you've previously run the E2E tests in release mode, you may need to delete the RNTester/build folder before rerunning detox build.
Building from source
Building the app on both iOS and Android means building the React Native framework from source. This way you're running the latest native and JS code the way you see it in your clone of the github repo.
This is different from apps created using react-native init which have a dependency on a specific version of React Native JS and native code, declared in a package.json file (and build.gradle for Android apps).